Biodegradable fire resistant foam

ABSTRACT

The instant invention is a fire protectant composition comprising water, a surfactant, a water-soluble polymer, casein, and a calcium salt. The compositions can be applied to materials such as wood in advance of a fire, and after application, the compositions are capable of retaining their fire protectant capacities for days, weeks or even months. This fire protectant composition is also biodegradable and nontoxic. It is also easily removed from the combustible material by a water wash once the fire danger is passes. If burned, the composition forms a “skin” which can be peeled off or removed by some other method such as pressure water spray or mechanical brushing.

RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.14/485,345, filed Sep. 12, 2014, entitled “Biodegradable Fire ResistantFoam”, which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present invention is directed to fire protective foams particularlyadapted for use in providing a protective coating to materials appliedin advance of a fire to prevent or reduce fire or heat damage.

BACKGROUND

Wildfires in the United States have increased in both frequency and sizedue to factors such as climate change and droughts, leading to increaseddryness in forest soils and vegetation. Additionally, the trends includesuburban sprawl which has caused more people to live and recreate inwildland areas, increasing the risk of human-caused fires and alsoincreasing the risk of damage to structures placed into wildland areas.Further, forestry practices since 1900 include suppression of naturalfires resulting in many wildland forests becoming more dense with treesand brush. Thus, fires become more destructive.

In many cases, wildland fires burn for many days or even weeks ormonths. The direction of the fire can be generally predicted andhomeowners in the potential path of the fire can be warned and asked toevacuate. Generally, protecting structures in wildlands includesfirefighters and homeowners constructing fire breaks, as well asfirefighters or homeowners spraying water onto flammable structures inadvance of a fire. Water has certain advantages in firefighting bycooling flammable materials and also displacement of oxygen that isnecessary for combustion of fuel. However, once homeowners areevacuated, they are unable to continue spraying water onto theirstructures.

Water evaporates quickly from dry materials. Further, continuouslyspraying water on combustible materials such as a home islabor-intensive, taking up firefighter's time that is better spentelsewhere, and dangerous to firefighters as well when the fire isnearby.

It would be desirable to provide to homeowners (and firefighters) with afire protectant product that can be applied to potentially combustiblematerials in advance of a fire or evacuation order, which would alsostay intact on the combustible material for a period of days to weeks,and provide excellent fire protection during that entire time withoutfurther attention or application. It is also desirable that the fireprotectant product would retain its fire protecting function afterapplication, even after drying or dehydration of the product. It wouldalso be desirable that the fire protectant product would bebiodegradable and nontoxic, and also that it can be easily removed fromthe combustible material by a water wash once the fire danger is passes,or easily removed from the material once it has been combusted.

Firefighting foams have been used for many years. Firefighting foams canwork by suppressing and preventing air from mixing with flammablevapors, separating flames from the fuel's surface, and cooling the fueland its surface through the action of water in the form. The foam iscreating by mechanically mixing air with a surfactant and othermaterials in water.

Hydrolyzed protein surfactant foams are known for fighting fires and aremade from hydrolyzed granular keratin proteins (hoof and horn meal,chicken feathers, etc.). They include stabilizing additives andinhibitors to prevent corrosion, resist bacterial decomposition and tocontrol viscosity. Fluoroprotein foams have fluorochemical surfactantswhich enhance performance by providing faster knockdown and better fueltolerance. Film forming fluoroprotein foam (FFFP) that are designed tocombine the fuel tolerance with increased knockdown power. Aqueous filmforming foams AFFF provides fast knockdown of hydrocarbon fuels. Alcoholresistant film forming fluoroprotein foams (AR-FFFP) are produced fromprotein foam, fluorochemical surfactants and polysaccharide polymers.They are capable of producing a tough membrane that separates the foamfrom the fuel and prevents the destruction of the foam blanket.

However, none of the foams currently available provide the combinationof properties to make a fire protectant product that can be applied topotentially combustible materials in advance of a fire or evacuationorder, that will remain intact on the combustible material for a periodof days to weeks, and provide excellent fire protection during thatentire time without further attention or application, and which is alsobiodegradable, nontoxic, and can be easily rinsed off when fireprotection is no longer needed.

The present invention is directed toward overcoming one or more of theproblems discussed above.

SUMMARY OF THE EMBODIMENTS

Various modifications and additions can be made to the embodimentsdiscussed without departing from the scope of the invention. Forexample, while the embodiments described above refer to particularfeatures, the scope of this invention also included embodiments havingdifferent combination of features and embodiments that do not includeall of the above described features.

In one embodiment, the present invention includes a fire protectantcomposition, comprising: water, a surfactant, a water-soluble polymer,casein, and a calcium salt. In some embodiments, the surfactant issodium dodecyl sulfate (SDS), the water soluble polymer iscarboxymethylcellulose (CMC), the calcium salt is Ca₃(PO₄)₂. The amountof SDS can be in an amount of about 20 g/L to about 65 g/L, the amountof CMC can be in an amount of from about 30 g/L to about 82 g/L, theamount of Ca₃(PO₄)₂ can be in an amount of 110 g/L to about 220 g/L, andthe casein can be in an amount of between about 25 g/L to about 75 g/L.

The present invention also includes a method to prevent fire damage to amaterial, comprising: applying the composition of the invention to amaterial prior to application of any heat or flame, wherein thecomposition is capable of preventing fire damage when heat or flame isapplied to the material. The composition can be applied in a ratio ofabout 100-150 square feet per gallon of composition, and applied priorto the application of heat or flame, including up to one hour previous,one day previous, three days previous, or a week or more previous.

Methods of the invention also include a method of making compositions ofthe present invention, which includes the steps of adding CMC powder towater and mixing until the CMC is fully hydrated; and adding thesurfactant, the casein, and the calcium salt and mixing until fullymixed.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of particularembodiments may be realized by reference to the remaining portions ofthe specification and the drawings, in which like reference numerals areused to refer to similar components. In some instances, a sub-label isassociated with a reference numeral to denote one of multiple similarcomponents. When reference is made to a reference numeral withoutspecification to an existing sub-label, it is intended to refer to allsuch multiple similar components.

FIG. 1 shows an untreated and unburned wood sample.

FIG. 2 shows the same board with one half lengthwise treated with(covered in) the fire protectant composition.

FIG. 3 shows the result on the treated portion of the board after heatwas applied using a MAP Gas welding torch to the treated portion of theboard.

FIG. 4 shows the result on the treated and untreated portion of theboard after heat was applied using a MAP Gas welding torch over thewhole board.

FIG. 5 shows the results after the after the wood of FIG. 4 was washedwith a garden watering hose attachment to remove the fire protectantcomposition.

FIG. 6 shows a close-up of the transition between the protected andunprotected portions of the wood following burning, after the burnedfire protectant composition was rinsed off.

FIG. 7 shows an end-view of the wood of FIG. 6.

DETAILED DESCRIPTION

In general, the instant invention relates to fire-protectantcomposition, e.g., a foam that can be sprayed or applied on surfaces inadvance of a fire, even days or weeks in advance of the fire, which willprotect those surfaces from damage from the fire or heat.

The instant invention is a fire protectant composition which optionally,can be sprayed on combustible materials in advance of a fire. Thecomposition avoids the need for constant water spraying to prevent thematerials from catching on fire, which can be difficult or impossiblefor a resource that can be in scarce supply in remote locations. Thefoams of the instant invention can also be used in an urban settingwhere buildings are close together and where heat and flames can spreadfrom building to building.

This fire protectant composition is also biodegradable and nontoxic. Itis also easily removed from the combustible material by a water washonce the fire danger is passes. If burned, the composition forms a“skin” which can be peeled off or removed by some other method such aspressure water spray or mechanical brushing.

While various aspects and features of certain embodiments have beensummarized above, the following detailed description illustrates a fewembodiments in further detail to enable one of skill in the art topractice such embodiments. The described examples are provided forillustrative purposes and are not intended to limit the scope of theinvention.

In the following description, for the purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of the described embodiments. It will be apparent to oneskilled in the art, however, that other embodiments of the presentinvention may be practiced without some of these specific details.Several embodiments are described and claimed herein, and while variousfeatures are ascribed to different embodiments, it should be appreciatedthat the features described with respect to one embodiment may beincorporated with other embodiments as well. By the same token, however,no single feature or features of any described or claimed embodimentshould be considered essential to every embodiment of the invention, asother embodiments of the invention may omit such features.

Unless otherwise indicated, all numbers used herein to expressquantities, dimensions, and so forth used should be understood as beingmodified in all instances by the term “about.” In this application, theuse of the singular includes the plural unless specifically statedotherwise, and use of the terms “and” and “or” means “and/or” unlessotherwise indicated. Moreover, the use of the term “including,” as wellas other forms, such as “includes” and “included,” should be considerednon-exclusive. Also, terms such as “element” or “component” encompassboth elements and components comprising one unit and elements andcomponents that comprise more than one unit, unless specifically statedotherwise.

In one embodiment, the present invention includes a fire protectantcomposition. In one embodiment, the fire protectant composition is afoam, which includes water, a surfactant, a water-soluble polymer,casein, and a calcium salt. The present invention also includes a fireprotectant composition, which consists of water, a surfactant, awater-soluble polymer, casein, and a calcium salt; the present inventionalso includes a fire protectant composition, which consists essentiallyof water, a surfactant, a water-soluble polymer, casein, and a calciumsalt.

“Protect” or “protectant” as used herein can refer to a material, suchas a foam as described herein, that either reduces or prevents damagefrom fire. Damage from fire can include, without limitation, damage fromheat, damage from direct combustion, damage from smoke or soot.

The fire protectant composition or foam can contain a surfactant whichis useful to enhance or create a foam. Surfactants useful for thepresent invention include organic compounds which are amphiphilic,containing both hydrophobic groups and hydrophilic groups. Thesurfactant should be used at above its critical micellular concentrationto ensure foaming. Surfactants can include a “tail” or hydrophobiccomponent which can include a hydrocarbon chain, a fluorocarbon chain,or siloxane chain, for example. Anionic surfactants contain anionicfunctional groups at their head, such as sulfate, sulfonate, phosphate,and carboxylates; these include ammonium lauryl sulfate, sodium laurylsulfate (SDS, sodium dodecyl sulfate) and the related alkyl-ethersulfates sodium laureth sulfate, also known as sodium lauryl ethersulfate (SLES), and sodium myreth sulfate. Anionic surfactants alsoinclude carboxylates such as alkyl carboxylates. Cationic surfactantscontain cationic functional groups at their head, such as a primaryamine or permanently changed quaternary ammonium cations, such asalkyltrimethylammonium salts, cetylpyridinium chloride (CPC),benzalkonium chloride (BAC), benzethonium chloride (BZT),5-bromo-5-nitro-1,3-dioxane, dimethyldioctadecylammonium chloride,cetrimonium bromide, dioctadecyldimethylammonium bromide, docusates suchas dioctyl sodium sulfosuccinate, perfluorooctanesulfonate (PFOS),perfluorobutanesulfonate, linear alkylbenzene sulfonates (LABs).Nonionic surfactants have nonionic head groups such as polyoxyethyleneglycol alkyl ethers, polyoxypropylene glycol alkyl ethers,polyoxyethylene glycol octylphenol ethers, polyoxyethylene glycolalkylphenol ethers, glycerol alkyl esters, polyoxyethylene glycolsorbitan alkyl esters, poloxamers.

In one embodiment, the surfactant is sodium dodecyl sulfate (SDS).

It has been found that amounts to use of the surfactant are what arenecessary to form adequate foams. In other words, surfactant can beevaluated by its ability as a foam-forming agent. A wide range ofamounts of surfactant can be used in the instant invention as describedabove. The amount of non-SDS surfactant should be adjusted to giveequivalent foam-forming activity as is present in the amounts of SDSgiven herein. In one embodiment, where the surfactant is SDS, the amountto use is about 2 cups of SDS per gallon of water, or about 43 g/L.Amounts to use can range from about 20 g/L to about 65 g/L. Amounts touse include from about 20 g/L to about 65 g/L, from about 25 g/L toabout 60 g/L, from about 30 g/L to about 55 g/L, from about 35 g/L toabout 50 g/L, from about 40 g/L to about 45 g/L. Other amounts includegreater than about 20 g/L, greater than about 25 g/L, greater than about30 g/L, greater than about 35 g/L, greater than about 40 g/L, or lessthan about 45 g/L, less than about 50 g/L, less than about 55 g/L, lessthan about 60 g/L, less than about 65 g/L. In alternative measurements,the amount of SDS to use is between about 1 cup of dry measure SDSpowder per gallon and about 3 cups dry measure SDS powder per gallon.

The fire protectant foam also contains a water-soluble polymer. Withoutbeing bound by theory, it is believed that the water soluble polymeracts as a thickener, phase and emulsion stabilizer (enhancing foampersistence), and water-holding agent.

Any known water soluble polymer which can enhance foam persistence canbe used in the present invention. Such polymers include hydrocolloidswhich include water swellable polymers and colloidal materials whichyield gel or viscous solution. Suitable polymers include polysaccharidepolymers which contain sugar units with anionic functionality such ascarboxyl or sulfate groups. Some examples of these sugar units areglucuronic acid, pyronic acid, gluconic acid, galactose sulfate andsugar units unique to specific gums. In addition to naturally occurringanionic functionality, synthetically modified polysaccharides are alsosuitable such as carboxymethyl cellulose. Representative examples ofsuitable water soluble polymers also include the following: xanthan gum,algin, welan gum, gellan gum, gum arabic, gum tragacanth, carrageenan,rhamsan gum, carboxymethyl cellulose, polysaccharide PS-7 and modifiedanionic starches.

In one embodiment, the water-soluble polymer is carboxymethylcellulose,also known as sodium carboxymethyl cellulose. Different preparations mayhave different degrees of substitution of the carboxymethyl groups, butit is generally in the range 0.6-0.95 derivatives per monomer unit.

Mixtures with other optional polysaccharides may be used and added tothe foam to improve foam stability by decreasing drainage, or to makethe concentrate more cost effective, or act synergistically with theprimary polymer to increase foam stability. These coadditives arenon-functional polysaccharides (nonionic) made up of sugar units such asglucose, mannose, anhydroglucose, galactose, rhamnose, andgalactopyranose. Synthetically modified anionic polysaccharides torender them non-ionic such as propylene glycol alginate, or cationicsuch as modified starch also apply. Examples of such optionalpolysaccharides are guar gum, locust bean gum, hydroxyethyl cellulose,hydroxypropyl cellulose, agar, propylene glycol alginate, scleroglucanand starch.

It has been found that amounts to use of the water soluble polymer arewhat are necessary to stabilize adequate foams, and/or provide adequatethickening. A wide range of amounts of water soluble polymer can be usedin the instant invention as described above. The amount of non-CMCsurfactant should be adjusted to give equivalent stabilization and/orthickening activity as is present in the amounts of CMC given herein.Where the surfactant is CMC, amounts to use can include about 1 cup pergallon, or about 42 g/L. Amounts to use can range from about 30 g/L toabout 82 g/L. In one embodiment, it is about 41 g/L. Amounts to useinclude from about 30 g/L to about 82 g/L, from about 32 g/L to about 75g/L, from about 34 g/L to about 70 g/L, from about 36 g/L to about 65g/L, from about 38 g/L to about 60 g/L. Other amounts include greaterthan about 30 g/L, greater than about 35 g/L, greater than about 40 g/L,or less than about 85 g/L, less than about 80 g/L, less than about 75g/L, less than about 70 g/L, less than about 65 g/L, less than about 60g/L, less than about 55 g/L, less than about 55 g/L, less than about 50g/L, or less than about 45 g/L. In alternative measurements, the amountof CMC to use is between about ¾ cup of dry measure CMC powder pergallon and about 2 cups dry measure CMC powder per gallon.

In other embodiments, water-soluble polymer or CMC that is pre-swelledmay be used in place of dry water soluble powder or CMC. Amounts to useshould be adjusted to provide equivalent amounts to the amounts providedherein for use of dry polymer.

The fire protectant composition or foam also includes a calcium salt.The calcium salt is useful for obtaining and forming the foam andstabilizing and forming a layer which protects the flammable material.It also provides heat resistance to the foam. Suitable calcium saltsinclude, but are not limited to, calcium chloride, calcium lactate,calcium sulfate, calcium carbonates, calcium phosphates, such asmonocalcium phosphate, dicalcium phosphate anhydrous, dicalciumphosphate dehydrate, α-tricalcium phosphate, octacalcium phosphate andtetracalcium phosphate, calcium glutareate, calcium malate, calciumcitrate, calcium gluconate, calcium glycerophosphate, calcium fumarate,calcium hydroxide, calcium oxide and combinations thereof. In oneembodiment, the calcium salt is Ca₃(PO₄)₂ (calcium phosphate tribasic).

It has been found that amounts to use of the calcium salt can vary. Awide range of amounts of calcium salt can be used in the instantinvention as described above. The amount of non-Ca₃(PO₄)₂ should beadjusted to give equivalent fire resistance activity as is present inthe amounts of Ca₃(PO₄)₂ given herein. Where the calcium salt isCa₃(PO₄)₂, amounts to use can be about 164 g/L, or about 3 cups pergallon. The amounts to use can range from about 110 g/L to about 220g/L. Amounts to use include from about 110 g/L to about 220 g/L, fromabout 120 g/L to about 210 g/L, from about 130 g/L to about 200 g/L,from about 140 g/L to about 190 g/L, from about 150 g/L to about 180g/L, or about 155 g/L to about 170 g/L. Other amounts include greaterthan about 110 g/L, greater than about 120 g/L, greater than about 130g/L, greater than about 140 g/L, greater than about 150 g/L, greaterthan about 160 g/L, or less than about 220 g/L, less than about 210 g/L,less than about 200 g/L, less than about 190 g/L, less than about 170g/L, or less than about 170 g/L. In alternative measurements, the amountof Ca₃(PO₄)₂ to use is between about 2 cup of dry measure Ca₃(PO₄)₂ pergallon and about 4 cups dry measure Ca₃(PO₄)₂ per gallon, oralternatively, about 3 cups.

The fire protectant composition or foam also includes casein. Casein isa milk protein which the instant inventors have found to create afire-protectant “skin” which provides an effective barrier to burning ofthe coated combustible material. Casein also provides additional textureto the foam, provides additional surfactant, and helps with adherence ofthe foam to the combustible material. Casein is the name for a number ofrelated phosphoproteins that are found in mammalian milk, commonly up to80% of the proteins in cow milk. Casein contains a fairly high number ofproline residues, which do not interact. There are also no disulfidebridges. As a result, it has relatively little tertiary structure. It isrelatively hydrophobic.

It has been found that amounts to use of casein can vary. A wide rangeof amounts of casein can be used in the instant invention as describedabove. Amounts to use can range from about 25 g/L to about 75 g/L. Inone embodiment, the amount to use is about 50 g/L, or about 2 cups pergallon. Amounts to use include from about 25 g/L to about 75 g/L, fromabout 30 g/L to about 70 g/L, from about 35 g/L to about 65 g/L, fromabout 40 g/L to about 60 g/L, from about 45 g/L to about 55 g/L. Otheramounts include greater than about 25 g/L, greater than about 30 g/L,greater than about 35 g/L, greater than about 40 g/L, greater than about45 g/L, or about 50 g/L, less than about 75 g/L, less than about 70 g/L,less than about 65 g/L, or less than about 60 g/L. In alternativemeasurements, the amount of casein to use is between about 1 cup of drymeasure casein per gallon and about 3 cups dry measure casein pergallon, or alternatively, about 2 cups.

The fire protectant compositions of the instant invention can be usedneat, or can be diluted for easier application. Dilutions include onepart foam to 0.5 parts water, one part foam to 0.75 parts water, onepart foam to one part water, one part foam to 1.5 parts water, one partfoam to 2 parts water, one part foam to 3 parts water, one part foam to4 parts water, one part foam to 5 parts water, one part foam to 6 partswater, one part foam to 7 parts water, one part foam to 8 parts water,one part foam to 10 parts water, or more. When the fire protectantcomposition is used as a diluted solution, the amount of water isincreased which can cause more movement of the foam when the combustiblematerial is heated.

Other components/excipients/additives are optionally included in thefire protectant compositions. For example, materials to balance the pHmay be added, such as buffers, acids, bases and the like. Antibacterialcomponents may be added, or components to aid in dissolution and/ordispersion. The foams of the invention may be stored prior to use forany length of time.

In another embodiment, the present invention also includes a method toprevent or reduce fire damage to materials, which includes the steps ofapplying the compositions of the instant invention to a material priorto application of any heat or flame. The foam then prevents or reducesfire damage from heat or flame from the material.

Suitable materials to apply the composition to include solid surfaceswhich may or may not be combustible. These surfaces may comprise,without limit, wood, particle board, hardboard, engineered wood, vinyl(polymers, including, without limitation, polyethylene, polystyrene,polyurethane), fiber cement, composites, mixtures thereof, and the like.Exemplary surfaces include home siding, shingles, decks, outbuildings,garages and the like.

The step of applying the composition e.g. foam can be by any methods asknown in the art. The composition may be painted on the surfaces orsprayed. If sprayed, the composition may be diluted in an amount thatretains the functionality of the composition upon application and issprayable.

The amount of composition e.g. foam to apply to obtain thefire-protectant properties includes wherein the foam is applied in aratio of about 100-150 square feet of surface per gallon of undilutedfoam. However, the ratio foam to surface can be adjusted depending onthe dilution of the foam (more foam per square foot may be desirablewhere the foam is more dilute), the amount of time fire protection isdesired for, the conditions (humid, dry), and the like.

In one aspect of the present invention, the fire protection is immediateand the fire protective composition, while hydrated, is effective atpreventing damage to structures from heat or flame. One surprisingaspect of the instant invention is that the composition remainsprotective against damage from heat or flame even after the water in thefoam has evaporated. Thus, the protective effect of the composition willremain even hours, days, or even weeks after application, and after thecomposition has dried. Without being bound by theory, it is believedthat the composition, e.g., the foam dries to a “skin” which providesflame and heat protection in the absence of water.

Therefore, in a surprising aspect of the invention, the composition canbe applied from mere minutes before exposure of a surface or material toflame and/or heat, or can be applied for up to weeks prior which isconvenient during a long evacuation. For example, the composition may beapplied more than one hour prior to application of heat or flame, morethan five hours prior to application of heat or flame, more than twelvehours prior to application of heat or flame, more than 18 hours prior toapplication of heat or flame, more than 24 hours prior to application ofheat or flame, more than 48 hours prior to application of heat or flame,more than 72 hours prior to application of heat or flame, more than 4days prior to application of heat or flame, more than 5 days prior toapplication of heat or flame, more than 6 days prior to application ofheat or flame, more than 7 days prior to application of heat or flame,more than 8 days prior to application of heat or flame, more than 9 daysprior to application of heat or flame, more than 10 days prior toapplication of heat or flame, more than 11 days prior to application ofheat or flame, more than 12 days prior to application of heat or flame,more than 13 days prior to application of heat or flame, more than 14days prior to application of heat or flame, more than 18 days prior toapplication of heat or flame, more than two weeks prior to applicationof heat or flame, more than three weeks prior to application of heat offlame, more than four weeks prior to application of heat or flame, morethan two months prior to application of heat or flame, more than threemonths prior to application of heat or flame.

In one embodiment, the composition remains protective of a surfaceagainst damage from heat or flame after application for at least onehour prior to application of heat or flame, at least five hours prior toapplication of heat or flame, at least twelve hours prior to applicationof heat or flame, at least 18 hours prior to application of heat orflame, at least 24 hours prior to application of heat or flame, at least48 hours prior to application of heat or flame, at least 72 hours priorto application of heat or flame, at least 4 days prior to application ofheat or flame, at least 5 days prior to application of heat or flame, atleast 6 days prior to application of heat or flame, at least 7 daysprior to application of heat or flame, at least 8 days prior toapplication of heat or flame, at least 9 days prior to application ofheat or flame, at least 10 days prior to application of heat or flame,at least 11 days prior to application of heat or flame, at least 12 daysprior to application of heat or flame, at least 13 days prior toapplication of heat or flame, at least 14 days prior to application ofheat or flame, at least 18 days prior to application of heat or flame,at least two weeks prior to application of heat or flame, at least threeweeks prior to application of heat of flame, at least four weeks priorto application of heat or flame, at least two months prior toapplication of heat or flame, at least three months prior to applicationof heat or flame.

In another embodiment, the present invention includes a method forforming a fire protective composition according to the invention. Inthis embodiment, dry water soluble polymer in appropriate amounts wasadded to the water and the mixture is stirred for a period of time tofully hydrate the polymer. After swelling of the water soluble polymer,the remaining components may be added in slowly to solution whilemixing/aerating solution until a foam is produced.

EXAMPLES

The following examples are provided for illustrative purposes only andare not intended to limit the scope of the invention.

Example 1

The foam formulation of this Example contained, per gallon of water, 2cups dry volume of sodium dodecyl sulfate (sodium lauryl sulfate)obtained from Chemistry Connection; 1 cup dry volumecarboxymethylcellulose (CMC, cellulose gum, obtained from PyroChemCorporation), 3 cup dry volume Ca₃(PO₄)₂ (calcium phosphate tribasic)(bone ash, ceramic calcium phosphate tribasic), and 2 cups casein, dryvolume (100% casein protein obtained from GNC Corporation). Per gallon,162 g SDS is added, 154 g CMC is added, 624 g Ca₃(PO₄)₂ is added, and190 g of casein is added. This is the equivalent of 43 g/L SDS, 41 g/LCMC, 164 g/L Ca₃(PO₄)₂, and 50.2 g/L casein.

To create the test formula, dry CMC in appropriate amounts was added tothe water. Due to the high viscosity of the CMC, the mixture was stirredto fully hydrate the cellulose until an ideal liquid texture wasachieved. Following the hydration of the CMC, the SDS and Ca₃(PO₄)₂ werealso added in slowly to solution while mixing/aerating solution until afoam was produced.

It was found that foams produced from mixtures of CMC, SDS and Ca₃(PO₄)₂did not produce ideal foams as the foam consistency was not appropriate(large droplet size, or bubble visibility) and the foams tended to losebubbles and volume upon heating, while not properly adhering tosurfaces. Thus, the results achieved did not provide long lastingprotection and the temperature resistance was not as high.

Adding the casein to the foam with appropriate amounts of CMC, SDS andCa₃(PO₄)₂ resulted in a foam with a thicker whipped-cream like texturewithout visible droplets (air bubbles).

Example 2

FIG. 1 shows the starting wood sample, including some small knots andimperfections in the wood, and a C shaped marking on one side. Theappearance is a standard 2×4 board, light in color, unfinished.

FIG. 2 shows the same board with one half lengthwise covered in theprotectant of Example 1 around 360 degrees of the surfaces. The coatingis about a half centimeter thick in some places, and as little as 1 mmin some of the edge areas. The amount of protectant applied was theequivalent of 1 gallon of the protectant for every 100-150 square feet.

FIG. 3 shows the results to the board after heat was applied using a MAPGas welding torch (3000+° F., much higher than wildfires or house firesreach at their peak) around the entire coated surface and top of theboard for approximately 6 minutes, or until 1 minute after the skin hadformed and expansion had stopped, and no more change from the heat wasoccurring.

FIG. 4 shows the results to the board shown in FIG. 3 when additionalheat was applied from the bottom of the protected area about 3 inchesdown the board and around 360 degrees of the surface, using the sameheat source, for approximately 30 seconds, or until the full surface hadscorched and the board caught fire, forming embers in the wood affectingthe structural properties of the board. The results showed that a “skin”that formed around the protected area became a black crust with smallcracks through which you can see the unaffected white protectant.Additionally, the coating had expanded as water evaporated out of thesolution forming a thicker more, even layer around the wood. Theunprotected portions of the wood where heat was applied have beenscorched black, with a rippled, warped appearance with areas of ashwhere the embers were. Also the perimeter/circumference of the wood inthe areas that were unprotected has visibly decreased 5 to 20% due tothe combustion of materials in the wood.

FIG. 5 shows the results after the wood of FIG. 4 was quickly washedwith a garden watering hose attachment rinsing of all the protectantleaving just the wood. It can be seen that the burned area that wasunprotected was completely black and charred, whereas, where the woodwas protected, the exact outline of completely unchanged wood can beseen. The bottom third of the board was never coated or subjected toheat, and the color, appearance and texture of the untouched portion andthe protected portion are identical. In the middle where the heat wasapplied the wood is completely black, or ashen and severely damaged.FIG. 6 shows a close-up for the transition between the protected andunprotected wood. FIG. 7 shows an end-view of the wood, showing that theperimeter/circumference of the wood in the areas that were unprotectedhas visibly decreased 5 to 20% due to the combustion of materials in thewood.

The foam of Example 1, in the tests, showed remarkable adherence to thewood even under very high temperatures, as well as the ability to form askin, or ash matrix, at the point of contact with heat while protectingthe under layer, effectively forming a shell around the surface. Thesetests were repeated several times to ensure repeatability of results.

The figures demonstrate that the compound provides complete flameprotection, even from prolonged exposure to heat drastically higher thanit would encounter in a wildfire or structure fire. While at the sametime, it washes off with only water and minimal pressure (when driedmore pressure may be required) leaving only soap bubbles and harmlessminerals and plant materials behind (flushing not required). While thepictures only demonstrate the compounds protective qualities, it can beinferred that its extinguishing properties would be similar, as onceapplied it occludes the heat and oxygen from the fuel source forming aninert barrier to subsequent exposure to flame in the process.

Example 3

In this example, the foam of Example 1 was applied to wood as accordingto Example 2. The foam-treated wood was then allowed to dry thoroughlyfor two weeks. After two weeks, the foam-treated wood was testedaccording to Example 2 with fire and showed similar if not increasedprotection, as it had less tendency to flow as the water evaporatedduring exposure from heat of the fire.

The description of the various embodiments has been presented forpurposes of illustration and description, but is not intended to beexhaustive or limiting of the invention to the form disclosed. The scopeof the present invention is limited only by the scope of the followingclaims. Many modifications and variations will be apparent to those ofordinary skill in the art. The embodiments described and shown in thefigures were chosen and described in order to explain the principles ofthe invention, the practical application, and to enable others ofordinary skill in the art to understand the invention for variousembodiments with various modifications as are suited to the particularuse contemplated. All references cited herein are incorporated in theirentirety by reference.

What is claimed is:
 1. A fire protectant composition, comprising: water,a surfactant comprising sodium dodecyl sulfate (SDS) in an amount ofbetween 20-65 g/L, a water-soluble polymer comprisingcarboxymethylcellulose (CMC) in an amount of between 30-82 g/L, caseinin an amount of between 25-75 g/L, and a calcium salt comprisingCa₃(PO₄)₂ in an amount of between 110-220 g/L.
 2. A compositioncomprising a combustible material coated with the fire protectantcomposition of claim
 1. 3. The fire protectant composition of claim 1,wherein the composition comprises about 43 g/L of SDS, about 41 g/L ofCMC, about 164 g/L of Ca₃(PO₄)₂, and about 50 g/L of casein.
 4. The fireprotectant composition of claim 1, wherein the calcium salt is a calciumphosphate salt derived from bone ash.
 5. A method of making thefire-protectant composition of claim 1, comprising a. adding thewater-soluble polymer to water and mixing until the water-solublepolymer is fully hydrated; b. adding the surfactant, casein, and thecalcium salt to the hydrated water-soluble polymer and mixing untilfully mixed to yield the fire-protectant composition.